Big Ben, the historic clock in the centre of London, will be quiet for around 3 months while they carry out some very important repairs.

The clock has not been silent very often in the 157 years that it has been in use.

So just how much energy is used to keep Big Ben (or more specifically, the Great Bell) doing its thing? Let’s find out!


In the past, the face of the clock tower was lit up using gas light so that Londoners could see the time at all hours of the day. However, they were swapped out in the 1990s with energy saving lightbulbs.

These lightbulbs have a lifetime of 60,000 hours, that’s nearly 7 years!

The updates to the clock might include replacing the last round of energy saving bulbs with even more efficient types; lightbulbs are constantly being developed to use less and less energy and to last longer.

There could even be plans in the future to use solar panels, not only on Big Ben to power its lights, but also on the roof of the Houses of Parliament.

inside Big Ben


The only energy used to ding the bell comes from a clever mechanism inside that relies on the weight of the bell and gravity!

View this animation which explains how the clock works

Rather than the bells swinging, as you would to ring a bell in your hand, the bells in Big Ben stay still while being hit with hammers to mark the hours.

If you would like to know more about the famous clock and tower, head over to this BBC article.